1. Field of the Invention
The present invention relates to a probe card for measuring electrical properties of a semiconductor device such as an LSI chip and the like.
2. Description of the Prior Art
A conventional probe card is classified into a horizontal type referred to as a cantilever type and a vertical type referred to as a perpendicular type. The horizontal type probe card is not suitable for simultaneous measurement of a plurality of chips involved in a large-scale high integration of current LSI chips and multiplexing of a tester. The vertical type probe card, on the other hand, is suitable for simultaneous measurement of a plurality of chips since a greater number of probe cards can be used and since the degree of freedom in arranging the probe is high.
In examining the semiconductor device, a plurality of chips needs to be simultaneously measured and probe cards having high electrical contact stability, high performance, and high reliability are required even if the number of electrodes of the probe card used is further increased.
Therefore, the vertical type probe card configured as shown in FIG. 17 has been proposed. In such vertical type probe card, a main substrate 1′ including a first main surface 1a′ with a plurality of first connecting electrodes 4′ arranged on a surface connecting with an electrical pad of a measuring device and a second main surface 1b′ with a second connecting electrode 5′ conducting with the first connecting electrode via a wire; a space transformer 2′ including a second main surface 2b′ with a plurality of fifth connecting electrodes 17′ connecting to an electrical pad of a measuring object and a first main surface 2a′ with a fourth connecting electrode 16′ conducting with the fifth connecting electrode 17′ via a wire; and a supporting substrate 25 arranged between the main substrate 1′ and the space transformer 2′ are provided. Further, a connecting pin 7′ lying across the supporting substrate and bent in an arched shape is provided, where one tip of the connecting pin 7′ contacts the second connecting electrode 5′ of the main substrate 1′ and the other tip contacts the fourth connecting electrode 16′ of the space transformer 2′.
However, in this type of probe card configured with the main substrate 1′, the space transformer 2′, the connecting pin 7′ conducting the opposing electrodes of the main substrate and the space transformer, and the supporting substrate supporting the connecting pin 7′, there are at least two points for electrical bias contact, the point of the second main surface of the main substrate 1′ and the tip of the connecting pin 7′ and the point of the first main surface of the space transformer 2′ and the other tip of the connecting pin 7′, and thus, conduction failure tends to occur as a whole. Further, since the connecting pin 7′ formed in a bent state tends to be long and is supported by the supporting substrate in a state having unequal direction, inclination and the like, the position of the tip of the connecting pin 7′ becomes inaccurate, and a greater number of conduction failures occur.